Extension Study of Idursulfase-IT Along With Elaprase in Children and Adults With Hunter Syndrome and Cognitive Impairment

Inclusion Criteria:

1. The participant must have completed end of study assessments in studies HGT-HIT-046 [NCT01506141] or SHP609-302 [NCT02412787] and received a clinical benefit fromidursulfase-IT in the opinion of the investigator.
2. The participant, or participant's legally designated representative, must have beeninformed of the nature of this open-label extension and must have voluntarily signedan Institutional Review Board (IRB)/Independent Ethics Committee (IEC) approvedinformed consent form after all relevant aspects of the study have been explained anddiscussed. Written consent of the participant's legally designated representative (ifapplicable) and the participant's consent/assent, as relevant, must be obtained.
3. The participant has continued to receive elaprase on a regular basis in studiesHGT-HIT-046 or SHP609-302.

Exclusion Criteria:

1. The participant has experienced, in the opinion of the investigator, a safety ormedical issue that contraindicates treatment with idursulfase-IT, including, but notlimited to, uncontrolled seizure disorder, bleeding disorder, and clinically relevanthypertension.
2. The participant has clinically relevant intracranial hypertension.
3. The participant is enrolled in another clinical study, other than studies HGT-HIT-046or SHP609-302, that involves clinical investigations or use of any investigationalproduct (drug or [intrathecal/spinal] device) within 30 days prior to study enrolmentor at any time during the study.